CN112669776B - Pixel circuit, driving method thereof and display panel - Google Patents
Pixel circuit, driving method thereof and display panel Download PDFInfo
- Publication number
- CN112669776B CN112669776B CN202110085498.6A CN202110085498A CN112669776B CN 112669776 B CN112669776 B CN 112669776B CN 202110085498 A CN202110085498 A CN 202110085498A CN 112669776 B CN112669776 B CN 112669776B
- Authority
- CN
- China
- Prior art keywords
- unit
- electrically connected
- initialization
- light
- control
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Control Of El Displays (AREA)
- Control Of Indicators Other Than Cathode Ray Tubes (AREA)
- Electroluminescent Light Sources (AREA)
Abstract
The invention provides a pixel circuit, a driving method thereof and a display panel. The pixel circuit includes a storage unit, a driving unit, a light emitting unit, a first initializing unit, a second initializing unit, and a third initializing unit. In the first stage, the first initialization unit is used for initializing the control end of the driving unit, and the second initialization unit is used for initializing the first end of the light-emitting unit; in the second stage, the third initialization unit is used for continuously initializing the first end of the light-emitting unit. The invention sets two initialization ways started by different control signals between the light-emitting unit and the initialization voltage input end, so that the light-emitting unit can be initialized in two stages, and the initialization time is prolonged, thereby the organic light-emitting diode is more completely initialized, and the display quality can be improved.
Description
Technical Field
The present invention relates to the field of display technologies, and in particular, to a pixel circuit, a driving method of the pixel circuit, and a display panel.
Background
The OLED (Organic Light-Emitting Diode) display is considered as a new application technology of the next-generation flat panel display, and the OLED display has the excellent characteristics of self-luminescence, no need of a backlight source, high contrast, thin thickness, wide viewing angle, fast reaction speed, applicability to a flexible panel, wide use temperature range, simple structure and process, and the like.
With the increasing proportion of games occupied in the life of people, especially for mobile phone games, the requirement of people on the multifunction of mobile phones is also increasing. To achieve a better visual experience, high refresh frequency displays are becoming more prevalent. The high refresh rate and the large-size screen shorten the line period, shorten the writing time, and the insufficient writing time can cause the problems of partial black and bright, uneven display and the like; meanwhile, the initialization time of the organic light emitting diode is shortened, which causes insufficient initialization and also causes the problems of poor display effects such as smear, black and partial brightness.
Disclosure of Invention
In view of the above technical problems, the present invention provides a pixel circuit, a driving method thereof, and a display panel.
The invention provides a pixel circuit which comprises a storage unit, a driving unit and a light-emitting unit, wherein a first end of the storage unit is electrically connected with a first voltage input end of the pixel circuit, a second end of the storage unit is electrically connected with a control end of the driving unit, and the driving unit is used for driving and controlling the light-emitting unit to emit light according to the voltage of the control end of the driving unit and a first power supply voltage input by the first voltage input end. The pixel circuit further comprises a first scanning signal input end, a second scanning signal input end, an initialization voltage input end, a first initialization unit, a second initialization unit and a third initialization unit; the control end of the first initialization unit is electrically connected with the first scanning signal input end, the first end of the first initialization unit is electrically connected with the control end of the driving unit, and the second end of the first initialization unit is electrically connected with the initialization voltage input end; the control end of the second initialization unit is electrically connected with the first scanning signal input end, the first end of the second initialization unit is electrically connected with the initialization voltage input end, and the second end of the second initialization unit is electrically connected with the first end of the light-emitting unit; the control end of the third initialization unit is electrically connected with the second scanning signal input end, the first end of the third initialization unit is electrically connected with the initialization voltage input end, and the second end of the third initialization unit is electrically connected with the first end of the light-emitting unit; in the first stage, the first initialization unit is used for initializing the control end of the driving unit, and the second initialization unit is used for initializing the first end of the light-emitting unit; in the second stage, the third initialization unit is used for continuously initializing the first end of the light-emitting unit.
Preferably, in the first phase, the first initializing unit and the second initializing unit are respectively controlled by the input signal of the first scanning signal input terminal to be turned on, the initializing voltage input by the initializing voltage input terminal is written into the control terminal of the driving unit through the turned-on first initializing unit, and the initializing voltage input by the initializing voltage input terminal is written into the first terminal of the light emitting unit through the turned-on second initializing unit; in the second stage, the third initializing unit is controlled by the input signal of the second scanning signal input end to be conducted, and the initializing voltage input by the initializing voltage input end is written into the first end of the light-emitting unit through the conducted third initializing unit.
Preferably, the pixel circuit further comprises a data voltage input terminal, a data writing unit and a threshold voltage compensation unit; the control end of the data writing unit is electrically connected with the second scanning signal input end, the first end of the data writing unit is electrically connected with the first end of the driving unit, and the second end of the data writing unit is electrically connected with the data voltage input end; the control end of the threshold voltage compensation unit is electrically connected with the second scanning signal input end, the first end of the threshold voltage compensation unit is electrically connected with the control end of the driving unit, and the second end of the threshold voltage compensation unit is electrically connected with the second end of the driving unit; in the second stage, the data writing unit and the threshold voltage compensation unit are respectively controlled by the input signal of the second scanning signal input end to be conducted, and the data voltage input by the data voltage input end is written into the control end of the driving unit through the conducted data writing unit, the conducting driving unit and the conducting threshold voltage compensation unit.
Further, the pixel circuit further comprises a light-emitting control signal input end, a first light-emitting control unit and a second light-emitting control unit; the control end of the first light-emitting control unit is electrically connected with the light-emitting control signal input end, the first end of the first light-emitting control unit is electrically connected with the first end of the driving unit, and the second end of the first light-emitting control unit is electrically connected with the first voltage input end; the control end of the second light-emitting control unit is electrically connected with the light-emitting control signal input end, the first end of the second light-emitting control unit is electrically connected with the first end of the light-emitting unit, and the second end of the second light-emitting control unit is electrically connected with the second end of the driving unit; in the third stage, the first light-emitting control unit and the second light-emitting control unit are respectively controlled by the input signal of the light-emitting control signal input end to be conducted, and the driving unit is used for driving the light-emitting unit to emit light.
Preferably, the storage unit includes a capacitor, the light emitting unit includes an organic light emitting diode, the driving unit includes a first transistor, the first initializing unit includes a second transistor, the second initializing unit includes a third transistor, and the third initializing unit includes a fourth transistor; the first end of the capacitor is electrically connected with the first voltage input end, and the second pole of the organic light-emitting diode is electrically connected with the second voltage input end of the pixel circuit; the grid electrode of the first transistor is electrically connected with the second end of the capacitor, and the first pole and the second pole of the first transistor are connected between the first voltage input end and the first pole of the organic light-emitting diode; the grid electrode of the second transistor is electrically connected with the first scanning signal input end, the first pole of the second transistor is electrically connected with the grid electrode of the first transistor, and the second pole of the second transistor is electrically connected with the initialization voltage input end; a gate electrode of the third transistor is electrically connected to the first scan signal input terminal, a first electrode of the third transistor is electrically connected to the initialization voltage input terminal, and a second electrode of the third transistor is electrically connected to the first electrode of the organic light emitting diode; a gate of the fourth transistor is electrically connected to the second scan signal input terminal, a first electrode of the fourth transistor is electrically connected to the initialization voltage input terminal, and a second electrode of the fourth transistor is electrically connected to the first electrode of the organic light emitting diode.
The invention relates to a driving method of a pixel circuit, wherein the pixel circuit comprises a storage unit, a driving unit and a light-emitting unit, a first end of the storage unit is electrically connected with a first voltage input end of the pixel circuit, a second end of the storage unit is electrically connected with a control end of the driving unit, and the driving unit is used for driving and controlling the light-emitting unit to emit light according to the voltage of the control end of the driving unit and a first power voltage input by the first voltage input end; the pixel circuit further comprises a first scanning signal input end, a second scanning signal input end, an initialization voltage input end, a first initialization unit, a second initialization unit and a third initialization unit; the control end of the first initialization unit is electrically connected with the first scanning signal input end, the first end of the first initialization unit is electrically connected with the control end of the driving unit, and the second end of the first initialization unit is electrically connected with the initialization voltage input end; the control end of the second initialization unit is electrically connected with the first scanning signal input end, the first end of the second initialization unit is electrically connected with the initialization voltage input end, and the second end of the second initialization unit is electrically connected with the first end of the light-emitting unit; the control end of the third initialization unit is electrically connected with the second scanning signal input end, the first end of the third initialization unit is electrically connected with the initialization voltage input end, and the second end of the third initialization unit is electrically connected with the first end of the light-emitting unit; the driving method of the pixel circuit includes: in the first stage, the first initialization unit is used for initializing the control end of the driving unit, and the second initialization unit is used for initializing the first end of the light-emitting unit; in the second stage, the third initialization unit is used for continuously initializing the first end of the light-emitting unit.
Preferably, in the first phase, the first initializing unit and the second initializing unit are respectively controlled by the input signal of the first scanning signal input terminal to be turned on, the initializing voltage input by the initializing voltage input terminal is written into the control terminal of the driving unit through the turned-on first initializing unit, and the initializing voltage input by the initializing voltage input terminal is written into the first terminal of the light emitting unit through the turned-on second initializing unit; in the second stage, the third initialization unit is controlled by the input signal of the second scanning signal input terminal to be conducted, and the initialization voltage input by the initialization voltage input terminal is written into the first end of the light emitting unit through the conducted third initialization unit.
Preferably, the pixel circuit further comprises a data voltage input terminal, a data writing unit and a threshold voltage compensation unit; the control end of the data writing unit is electrically connected with the second scanning signal input end, the first end of the data writing unit is electrically connected with the first end of the driving unit, and the second end of the data writing unit is electrically connected with the data voltage input end; the control end of the threshold voltage compensation unit is electrically connected with the second scanning signal input end, the first end of the threshold voltage compensation unit is electrically connected with the control end of the driving unit, and the second end of the threshold voltage compensation unit is electrically connected with the second end of the driving unit; the driving method of the pixel circuit includes: in the second stage, the data writing unit and the threshold voltage compensation unit are respectively controlled by the input signal of the second scanning signal input end to be conducted, and the data voltage input by the data voltage input end is written into the control end of the driving unit through the conducted data writing unit, the driving unit and the threshold voltage compensation unit.
Further, the pixel circuit further comprises a light-emitting control signal input end, a first light-emitting control unit and a second light-emitting control unit; the control end of the first light-emitting control unit is electrically connected with the light-emitting control signal input end, the first end of the first light-emitting control unit is electrically connected with the first end of the driving unit, and the second end of the first light-emitting control unit is electrically connected with the first voltage input end; the control end of the second light-emitting control unit is electrically connected with the light-emitting control signal input end, the first end of the second light-emitting control unit is electrically connected with the first end of the light-emitting unit, and the second end of the second light-emitting control unit is electrically connected with the second end of the driving unit; the driving method of the pixel circuit further includes: in the third stage, the first light-emitting control unit and the second light-emitting control unit are respectively controlled by the input signal of the light-emitting control signal input end to be conducted, and the driving unit is used for driving the light-emitting unit to emit light.
The present invention provides a display panel comprising a pixel circuit as described in any one of the above.
Compared with the prior art, the pixel circuit, the driving method thereof and the display panel provided by the invention have the advantages that two initialization ways started by different control signals are arranged between the light-emitting unit and the initialization voltage input end, so that the light-emitting unit can be initialized in two stages, the initialization time is prolonged, the light-emitting unit (such as an organic light-emitting diode) is initialized more completely, the phenomena of poor display such as smear, black and partial brightness can be improved, and the display quality of the display panel is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a schematic diagram of a pixel circuit according to an embodiment of the invention.
Fig. 2 is a schematic diagram of a pixel circuit according to another embodiment of the invention.
Fig. 3 is a schematic diagram of a pixel circuit according to another embodiment of the invention.
Fig. 4 is a schematic diagram of a pixel circuit according to still another embodiment of the invention.
Fig. 5 is a flowchart of a driving method of a pixel circuit according to an embodiment of the invention.
Fig. 6 is a flowchart of a driving method of a pixel circuit according to another embodiment of the invention.
Detailed Description
In order to further understand the objects, structures, features, and functions of the present invention, the following embodiments are described in detail.
It should be noted that although the terms "first," "second," "third," etc. may be used herein to describe various components, these components should not be limited by these terms; these terms are only used to distinguish one component from another.
It is to be noted that when a layer, region or component is referred to as being "electrically connected" or "coupled" to another layer, another region or another component, the layer, region or component may be "directly electrically connected or directly electrically coupled" to the other layer, another region or another component, or "indirectly electrically connected or indirectly electrically coupled" to the other layer, another region or another component with an intermediate layer, an intermediate region or an intermediate component interposed therebetween.
Referring to fig. 1, fig. 1 is a schematic diagram of a pixel circuit according to an embodiment of the invention. The pixel circuit 100 includes a memory unit 1, a driving unit 2 and a light emitting unit 3, wherein a first terminal of the memory unit 1 is electrically connected to a first voltage input terminal VDD of the pixel circuit 100, a second terminal of the memory unit 1 is electrically connected to a control terminal 20 of the driving unit 2, and the driving unit 2 is configured to drive and control the light emitting unit 3 to emit light according to a voltage of the control terminal 20 of the driving unit 2 and a first power voltage input by the first voltage input terminal VDD. The memory unit 1 can be used to store the voltage of the control terminal 20 of the driving unit 2.
The pixel circuit 100 further includes a first scan signal input terminal S1, a second scan signal input terminal S2, an initialization voltage input terminal VREF, a first initialization unit 4, a second initialization unit 5, and a third initialization unit 6.
The control terminal of the first initialization unit 4 is electrically connected to the first scan signal input terminal S1, the first terminal of the first initialization unit 4 is electrically connected to the control terminal 20 of the driving unit 2, and the second terminal of the first initialization unit 4 is electrically connected to the initialization voltage input terminal VREF.
The control terminal of the second initializing unit 5 is electrically connected to the first scan signal input terminal S1, the first terminal of the second initializing unit 5 is electrically connected to the initializing voltage input terminal VREF, and the second terminal of the second initializing unit 5 is electrically connected to the first terminal of the light emitting unit 3.
The control terminal of the third initializing unit 6 is electrically connected to the second scanning signal input terminal S3, the first terminal of the third initializing unit 6 is electrically connected to the initializing voltage input terminal VREF, and the second terminal of the third initializing unit 6 is electrically connected to the first terminal of the light emitting unit 3.
In the first phase, the first initialization unit 4 is used to initialize the control terminal 20 of the driving unit 2, and the second initialization unit 5 is used to initialize the first terminal of the light emitting unit 3. In the second phase, the third initializing unit 6 is used to continue initializing the first terminal of the light emitting unit 3.
According to the embodiment of the present invention, in the first stage, the input signal of the first scan signal input terminal S1 corresponds to an active level, the first initializing unit 4 and the second initializing unit 5 controlled thereby are both turned on, the turned-on first initializing unit 4 provides the initializing signal of the initializing voltage input terminal VREF to the control terminal 20 of the driving unit 2 to initialize the driving unit 2, and the turned-on second initializing unit 5 provides the initializing signal of the initializing voltage input terminal VREF to the first terminal of the light emitting unit 3 to initialize the light emitting unit 3; in the second stage, the input signal of the second scan signal input terminal S2 corresponds to an active level, the controlled third initialization unit 6 is turned on, and the turned-on third initialization unit 6 provides the initialization signal of the initialization voltage input terminal VREF to the first terminal of the light emitting unit 3, so as to continue initializing the light emitting unit 3. In this way, the light emitting unit 3 is initialized in both the first stage and the second stage, i.e., in the period when the input signal of the first scan signal input terminal S1 is at the active level and in the period when the input signal of the second scan signal input terminal S2 is at the active level, so that the initialization time for the light emitting unit 3 is increased.
In one embodiment, in the first phase, the first initializing unit 4 and the second initializing unit 5 are respectively controlled by the input signal of the first scan signal input terminal S1 to be turned on, the initializing voltage inputted from the initializing voltage input terminal VREF is written into the control terminal 20 of the driving unit 2 through the turned-on first initializing unit 4, and the initializing voltage inputted from the initializing voltage input terminal VREF is written into the first terminal of the light emitting unit 3 through the turned-on second initializing unit 5. In the second stage, the third initializing unit 6 is controlled by the input signal of the second scan signal input terminal S2 to be turned on, and the initializing voltage inputted from the initializing voltage input terminal VREF is written into the first terminal of the light emitting unit 3 through the turned-on third initializing unit 6.
In practical applications, the second terminal of the light emitting unit 3 is electrically connected to the second voltage input terminal VSS of the pixel circuit 100.
Referring to fig. 2, fig. 2 is a schematic diagram of a pixel circuit according to another embodiment of the invention. Compared with the previous embodiments, the pixel circuit described in this embodiment further includes a data voltage input terminal VDATA, a data writing unit 7, and a threshold voltage compensation unit 8. The control terminal of the data writing unit 7 is electrically connected to the second scan signal input terminal S2, the first terminal of the data writing unit 7 is electrically connected to the first terminal 21 of the driving unit 2, and the second terminal of the data writing unit 7 is electrically connected to the data voltage input terminal VDATA. The control terminal of the threshold voltage compensation unit 8 is electrically connected to the second scan signal input terminal S2, the first terminal of the threshold voltage compensation unit 8 is electrically connected to the control terminal 20 of the driving unit 2, and the second terminal of the threshold voltage compensation unit 8 is electrically connected to the second terminal 22 of the driving unit 2. In the second stage, the data writing unit 7 and the threshold voltage compensation unit 8 are respectively controlled by the input signal of the second scan signal input terminal S2 to be turned on, and the data voltage inputted from the data voltage input terminal VDATA is written into the control terminal 20 of the driving unit 2 through the turned-on data writing unit 7, the driving unit 2 and the threshold voltage compensation unit 8.
According to the embodiment of the present invention, in the second stage, the input signal at the second scan signal input terminal S2 corresponds to an active level, the controlled data writing unit 7 and the threshold voltage compensation unit 8 are both turned on, and the turned-on data writing unit 7, the driving unit 2 and the threshold voltage compensation unit 8 provide the data voltage input from the data voltage input terminal VDATA to the control terminal 20 of the driving unit 2, so as to perform data writing compensation on the driving unit 2.
Referring to fig. 3, fig. 3 is a schematic diagram of a pixel circuit according to another embodiment of the invention. Compared with the previous embodiments, the pixel circuit described in this embodiment further includes an emission control signal input terminal EM, a first emission control unit 91, and a second emission control unit 92. The control terminal of the first light emission control unit 91 is electrically connected to the light emission control signal input terminal EM, the first terminal of the first light emission control unit 91 is electrically connected to the first terminal 21 of the driving unit 2, and the second terminal of the first light emission control unit 91 is electrically connected to the first voltage input terminal VDD. A control end of the second light-emitting control unit 92 is electrically connected to the light-emitting control signal input end EM, a first end of the second light-emitting control unit 92 is electrically connected to a first end of the light-emitting unit 3, and a second end of the second light-emitting control unit 92 is electrically connected to the second end 22 of the driving unit 2. In the third stage, the first light-emitting control unit 91 and the second light-emitting control unit 92 are respectively controlled by the input signal of the light-emitting control signal input terminal EM to be turned on, the second initialization unit 5 is turned off, and the driving unit 2 is used for driving the light-emitting unit 3 to emit light.
According to the embodiment of the present invention, in the third stage, the input signal of the light-emitting control signal input end EM corresponds to an active level, the first light-emitting control unit 91 and the second light-emitting control unit 92 controlled by the active level are both turned on, and the driving unit 2 is in a saturation state to drive the light-emitting unit 3 to emit light. In the third phase, there is no active level in the input signal of the first scan signal input terminal S1, and the second initialization unit 5 controlled thereby is turned off.
Referring to fig. 4, fig. 4 is a schematic diagram of a pixel circuit according to still another embodiment of the invention. Compared with the previous embodiments, in the pixel circuit described in this embodiment, the storage unit includes a capacitor C1, the light emitting unit includes an organic light emitting diode OLED, the driving unit includes a first transistor M1, the first initialization unit includes a second transistor M2, the second initialization unit includes a third transistor M3, and the third initialization unit includes a fourth transistor M4. A first terminal of the capacitor C1 is electrically connected to the first voltage input terminal VDD, and a second terminal of the organic light emitting diode OLED is electrically connected to the second voltage input terminal VSS of the pixel circuit. The gate of the first transistor M1 is electrically connected to the second end of the capacitor C1, and the first pole and the second pole of the first transistor M1 are connected between the first voltage input terminal VDD and the first pole of the organic light emitting diode OLED. The gate of the second transistor M2 is electrically connected to the first scan signal input terminal S1, the first pole of the second transistor M2 is electrically connected to the gate of the first transistor M1, and the second pole of the second transistor M2 is electrically connected to the initialization voltage input terminal VREF. A gate electrode of the third transistor M3 is electrically connected to the first scan signal input terminal S1, a first electrode of the third transistor M3 is electrically connected to the initialization voltage input terminal VREF, and a second electrode of the third transistor M3 is electrically connected to the first electrode of the organic light emitting diode OLED. A gate electrode of the fourth transistor M4 is electrically connected to the second scan signal input terminal S2, a first electrode of the fourth transistor M4 is electrically connected to the initialization voltage input terminal VREF, and a second electrode of the fourth transistor M4 is electrically connected to the first electrode of the organic light emitting diode OLED.
In the stage where the input signal of the first scan signal input terminal S1 is at the active level and the input signal of the second scan signal input terminal S2 is at the active level, the organic light emitting diode OLED is initialized, and compared with the prior art where the OLED is initialized in only one stage (for example, during the period where only the S2 input signal is at the active level), the initialization time can be doubled, so that the OLED is initialized more completely, and the display problems of smear and black bias brightness can be improved.
With continued reference to fig. 4, in the pixel circuit according to the different embodiments, the data writing unit includes a fifth transistor M5, and the threshold voltage compensation unit includes a sixth transistor M6. A gate of the fifth transistor M5 is electrically connected to the second scan signal input terminal S2, a first pole of the fifth transistor M5 is electrically connected to the first pole of the first transistor M1, and a second pole of the fifth transistor M5 is electrically connected to the data voltage input terminal VDATA. A gate of the sixth transistor M6 is electrically connected to the second scan signal input terminal S2, a first pole of the sixth transistor M6 is electrically connected to the gate of the first transistor M1, and a second pole of the sixth transistor M6 is electrically connected to the second pole of the first transistor M1.
With reference to fig. 4, in the pixel circuit according to the different embodiments, the first light-emitting control unit includes a seventh transistor M7, and the second light-emitting control unit includes an eighth transistor M8. A gate of the seventh transistor M7 is electrically connected to the emission control signal input terminal EM, a first pole of the seventh transistor M7 is electrically connected to the first pole of the first transistor M1, and a second pole of the seventh transistor M7 is electrically connected to the first voltage input terminal VDD. A gate of the eighth transistor M8 is electrically connected to the emission control signal input terminal EM, a first pole of the eighth transistor M8 is electrically connected to the first pole of the organic light emitting diode OLED, and a second pole of the eighth transistor M8 is electrically connected to the second pole of the first transistor M1.
According to the embodiment of the present invention, each of the transistors may be a Thin Film Transistor (TFT) or a Metal Oxide Semiconductor Field Effect Transistor (MOSFET), the control electrodes of the transistors are gates of the transistors, and according to the type of the transistors and the difference of input signals, the first electrodes of the transistors may be used as the source or the drain of the transistor, and the second electrodes may be used as the drain or the source of the transistor; in practical applications, the type of the transistor needs to be designed according to practical application environments, and the invention is not limited thereto.
The transistors M1 to M8 may be the same type of transistors, such as P-type transistors or N-type transistors, or different types of transistors may be used; in practical applications, the types of the first to eighth transistors may be determined according to practical application environments, and are not limited herein. It should be noted that the P-type transistor is turned off under the action of a high level and turned on under the action of a low level; the N-type transistor is switched on under the action of a high level and is switched off under the action of a low level; therefore, the active level according to the present invention refers to a level at which the corresponding transistor can be turned on, and is not limited to a high level and a low level.
The voltage of the first voltage input terminal VDD is generally a positive value, the voltage of the first voltage input terminal VSS is generally a ground or negative value, and the voltage of the initialization voltage input terminal VREF is generally a negative value. In practical applications, the specific values may be designed and determined according to practical application situations, and the present invention is not limited thereto. By taking VREF voltage as-3V as an example, the method of the invention is utilized to initialize the OLED for two time periods, and finally the initialization voltage can reach-2.99V, and the effect is obviously better than that of the prior art.
The first end of the light emitting unit 3 is a positive electrode (or called anode), and the second end is a negative electrode (or called cathode). Also, the light emitting unit 3 may be an organic light emitting diode that realizes light emission by a current when the transistor of the driving unit 2 is in a saturated state.
Referring to fig. 5 in combination, fig. 5 is a flowchart of a driving method of a pixel circuit according to an embodiment of the invention. The pixel circuit comprises a storage unit, a driving unit, a light-emitting unit, a first scanning signal input end, a second scanning signal input end, an initialization voltage input end, a first initialization unit, a second initialization unit and a third initialization unit; the first end of the storage unit is electrically connected with the first voltage input end of the pixel circuit, the second end of the storage unit is electrically connected with the control end of the driving unit, and the driving unit is used for driving and controlling the light-emitting unit to emit light according to the voltage of the control end of the driving unit and the first power supply voltage input by the first voltage input end; the control end of the first initialization unit is electrically connected with the first scanning signal input end, the first end of the first initialization unit is electrically connected with the control end of the driving unit, and the second end of the first initialization unit is electrically connected with the initialization voltage input end; the control end of the second initialization unit is electrically connected with the first scanning signal input end, the first end of the second initialization unit is electrically connected with the initialization voltage input end, and the second end of the second initialization unit is electrically connected with the first end of the light-emitting unit; the control end of the third initialization unit is electrically connected with the second scanning signal input end, the first end of the third initialization unit is electrically connected with the initialization voltage input end, and the second end of the third initialization unit is electrically connected with the first end of the light-emitting unit. The driving method of the pixel circuit includes the steps of:
in a first stage, the first initializing unit is configured to initialize the control terminal of the driving unit, and the second initializing unit is configured to initialize the first terminal of the light emitting unit.
Optionally, in the first phase of step 101, the first initializing unit and the second initializing unit are respectively controlled by the input signal of the first scanning signal input terminal to be turned on, the initializing voltage input by the initializing voltage input terminal is written into the control terminal of the driving unit through the turned-on first initializing unit, and the initializing voltage input by the initializing voltage input terminal is written into the first terminal of the light emitting unit through the turned-on second initializing unit. In the second phase of step 102, the third initializing unit is controlled by the input signal of the second scan signal input terminal to be turned on, and the initializing voltage inputted from the initializing voltage input terminal is written into the first end of the light emitting unit through the turned-on third initializing unit.
In one embodiment, the pixel circuit further includes a data voltage input terminal, a data writing unit, and a threshold voltage compensation unit; the control end of the data writing unit is electrically connected with the second scanning signal input end, the first end of the data writing unit is electrically connected with the first end of the driving unit, and the second end of the data writing unit is electrically connected with the data voltage input end; the control end of the threshold voltage compensation unit is electrically connected with the second scanning signal input end, the first end of the threshold voltage compensation unit is electrically connected with the control end of the driving unit, and the second end of the threshold voltage compensation unit is electrically connected with the second end of the driving unit. The driving method of the pixel circuit includes, in the second stage of step 102, the data writing unit and the threshold voltage compensation unit are respectively controlled by the input signal of the second scan signal input terminal to be turned on, and the data voltage input by the data voltage input terminal is written into the control terminal of the driving unit through the turned-on data writing unit, the turned-on driving unit and the turned-on threshold voltage compensation unit.
Referring to fig. 6 in combination, fig. 6 is a flowchart of a driving method of a pixel circuit according to another embodiment of the invention. Compared with the driving method of the pixel circuit of the previous embodiment, the pixel circuit of the present embodiment further includes a light emission control signal input terminal, a first light emission control unit, and a second light emission control unit; a control end of the first light emitting control unit is electrically connected with the light emitting control signal input end, a first end of the first light emitting control unit is electrically connected with a first end of the driving unit, and a second end of the first light emitting control unit is electrically connected with the first voltage input end; the control end of the second light-emitting control unit is electrically connected with the light-emitting control signal input end, the first end of the second light-emitting control unit is electrically connected with the first end of the light-emitting unit, and the second end of the second light-emitting control unit is electrically connected with the second end of the driving unit. The driving method of the pixel circuit further includes the steps of:
In an embodiment, in the third phase, the second initialization unit is turned off.
Based on the same or similar working principle, the descriptions in the embodiments of the pixel circuit are also applicable to the embodiments of the driving method of the pixel circuit, and therefore are not repeated herein. The driving method of the pixel circuit described above may be implemented by an integrated or discrete chip or circuit module.
The invention also provides a display panel comprising the pixel circuit according to any one of the above embodiments. In practical applications, the display panel may further include a signal line, a power line, and the like connected to the various input terminals.
The display panel may be an organic light emitting display panel. The display panel can be applied to display screens of various intelligent terminals such as mobile phones, tablet computers, displays and navigators, and can also be applied to various household appliances such as televisions, robots and monitors or equipment with a display function for industrial production.
According to the pixel circuit, the driving method thereof and the display panel, two initialization ways which are started by different control signals are arranged between the organic light emitting diode and the initialization voltage input end, so that the organic light emitting diode can be initialized in two stages, the initialization time is prolonged by one time, the organic light emitting diode is more completely initialized, the phenomena of poor display such as smear, partial brightness in black and the like can be improved, and the display quality of the display panel is improved.
The present invention has been described in relation to the above embodiments, which are only exemplary of the implementation of the present invention. Furthermore, the technical features mentioned in the different embodiments of the present invention described above can be combined with each other as long as they do not conflict with each other. It should be noted that the disclosed embodiments do not limit the scope of the invention. Rather, it is intended that all such modifications and variations be included within the spirit and scope of this invention.
Claims (10)
1. A pixel circuit comprises a storage unit, a driving unit and a light-emitting unit, wherein a first end of the storage unit is electrically connected with a first voltage input end of the pixel circuit, a second end of the storage unit is electrically connected with a control end of the driving unit, and the driving unit is used for driving and controlling the light-emitting unit to emit light according to the voltage of the control end of the driving unit and a first power voltage input by the first voltage input end; wherein the pixel circuit further comprises: the device comprises a first scanning signal input end, a second scanning signal input end, an initialization voltage input end, a first initialization unit, a second initialization unit and a third initialization unit;
the control end of the first initialization unit is electrically connected with the first scanning signal input end, the first end of the first initialization unit is electrically connected with the control end of the driving unit, and the second end of the first initialization unit is electrically connected with the initialization voltage input end;
the control end of the second initialization unit is electrically connected with the first scanning signal input end, the first end of the second initialization unit is electrically connected with the initialization voltage input end, and the second end of the second initialization unit is electrically connected with the first end of the light-emitting unit;
the control end of the third initialization unit is electrically connected with the second scanning signal input end, the first end of the third initialization unit is electrically connected with the initialization voltage input end, and the second end of the third initialization unit is electrically connected with the first end of the light-emitting unit;
in a first phase, the first initialization unit and the second initialization unit are respectively controlled by an input signal of the first scan signal input terminal, the controlled first initialization unit is used for initializing the control terminal of the driving unit, and the controlled second initialization unit is used for initializing the first terminal of the light emitting unit; in a second stage, the third initialization unit is controlled by the input signal of the second scan signal input terminal, the input signal of the second scan signal input terminal corresponds to an active level in the second stage, and the third initialization unit controlled by the second initialization unit is used for continuously initializing the first terminal of the light emitting unit.
2. The pixel circuit according to claim 1, wherein in the first phase, the first initializing unit and the second initializing unit are respectively controlled by an input signal of the first scan signal input terminal to be turned on, an initializing voltage input from the initializing voltage input terminal is written to the control terminal of the driving unit through the turned-on first initializing unit, and an initializing voltage input from the initializing voltage input terminal is written to the first terminal of the light emitting unit through the turned-on second initializing unit; in the second phase, the third initialization unit is controlled by the input signal of the second scanning signal input terminal to be turned on, and the initialization voltage input by the initialization voltage input terminal is written into the first end of the light emitting unit through the turned-on third initialization unit.
3. The pixel circuit according to claim 1, further comprising a data voltage input terminal, a data writing unit, and a threshold voltage compensation unit; the control end of the data writing unit is electrically connected with the second scanning signal input end, the first end of the data writing unit is electrically connected with the first end of the driving unit, and the second end of the data writing unit is electrically connected with the data voltage input end; the control end of the threshold voltage compensation unit is electrically connected with the second scanning signal input end, the first end of the threshold voltage compensation unit is electrically connected with the control end of the driving unit, and the second end of the threshold voltage compensation unit is electrically connected with the second end of the driving unit; in the second stage, the data writing unit and the threshold voltage compensation unit are respectively controlled by the input signal of the second scanning signal input end to be conducted, and the data voltage input by the data voltage input end is written into the control end of the driving unit through the conducted data writing unit, the conducting driving unit and the threshold voltage compensation unit.
4. The pixel circuit according to claim 3, further comprising a light emission control signal input terminal, a first light emission control unit, and a second light emission control unit; a control end of the first light emitting control unit is electrically connected with the light emitting control signal input end, a first end of the first light emitting control unit is electrically connected with a first end of the driving unit, and a second end of the first light emitting control unit is electrically connected with the first voltage input end; the control end of the second light-emitting control unit is electrically connected with the light-emitting control signal input end, the first end of the second light-emitting control unit is electrically connected with the first end of the light-emitting unit, and the second end of the second light-emitting control unit is electrically connected with the second end of the driving unit; in a third stage, the first light-emitting control unit and the second light-emitting control unit are respectively controlled by an input signal of the light-emitting control signal input end to be conducted, and the driving unit is used for driving the light-emitting unit to emit light.
5. The pixel circuit according to claim 1, wherein the storage unit includes a capacitor, the light emitting unit includes an organic light emitting diode, the driving unit includes a first transistor, the first initializing unit includes a second transistor, the second initializing unit includes a third transistor, and the third initializing unit includes a fourth transistor; a first end of the capacitor is electrically connected with the first voltage input end, and a second pole of the organic light emitting diode is electrically connected with the second voltage input end of the pixel circuit; a grid electrode of the first transistor is electrically connected with the second end of the capacitor, and a first pole and a second pole of the first transistor are connected between the first voltage input end and the first pole of the organic light-emitting diode; a gate of the second transistor is electrically connected to the first scan signal input terminal, a first pole of the second transistor is electrically connected to the gate of the first transistor, and a second pole of the second transistor is electrically connected to the initialization voltage input terminal; a gate electrode of the third transistor is electrically connected to the first scan signal input terminal, a first electrode of the third transistor is electrically connected to the initialization voltage input terminal, and a second electrode of the third transistor is electrically connected to the first electrode of the organic light emitting diode; a gate of the fourth transistor is electrically connected to the second scan signal input terminal, a first pole of the fourth transistor is electrically connected to the initialization voltage input terminal, and a second pole of the fourth transistor is electrically connected to the first pole of the organic light emitting diode.
6. A driving method of a pixel circuit comprises a storage unit, a driving unit and a light-emitting unit, wherein a first end of the storage unit is electrically connected with a first voltage input end of the pixel circuit, a second end of the storage unit is electrically connected with a control end of the driving unit, and the driving unit is used for driving and controlling the light-emitting unit to emit light according to the voltage of the control end of the driving unit and a first power voltage input by the first voltage input end; the pixel circuit is characterized by further comprising a first scanning signal input end, a second scanning signal input end, an initialization voltage input end, a first initialization unit, a second initialization unit and a third initialization unit; the control end of the first initialization unit is electrically connected with the first scanning signal input end, the first end of the first initialization unit is electrically connected with the control end of the driving unit, and the second end of the first initialization unit is electrically connected with the initialization voltage input end; the control end of the second initialization unit is electrically connected with the first scanning signal input end, the first end of the second initialization unit is electrically connected with the initialization voltage input end, and the second end of the second initialization unit is electrically connected with the first end of the light-emitting unit; the control end of the third initialization unit is electrically connected with the second scanning signal input end, the first end of the third initialization unit is electrically connected with the initialization voltage input end, and the second end of the third initialization unit is electrically connected with the first end of the light-emitting unit; the driving method of the pixel circuit includes:
in a first phase, the first initialization unit and the second initialization unit are respectively controlled by the input signal of the first scan signal input terminal, the controlled first initialization unit is used for initializing the control terminal of the driving unit, and the controlled second initialization unit is used for initializing the first terminal of the light emitting unit;
in a second stage, the third initialization unit is controlled by the input signal of the second scan signal input terminal, the input signal of the second scan signal input terminal corresponds to an active level in the second stage, and the third initialization unit controlled by the second initialization unit is used for continuously initializing the first terminal of the light emitting unit.
7. The method for driving the pixel circuit according to claim 6, wherein in the first stage, the first initializing unit and the second initializing unit are respectively controlled to be turned on by an input signal of the first scanning signal input terminal, an initializing voltage input from the initializing voltage input terminal is written to the control terminal of the driving unit through the turned-on first initializing unit, and an initializing voltage input from the initializing voltage input terminal is written to the first terminal of the light emitting unit through the turned-on second initializing unit; in the second phase, the third initialization unit is controlled by the input signal of the second scanning signal input terminal to be turned on, and the initialization voltage input by the initialization voltage input terminal is written into the first end of the light emitting unit through the turned-on third initialization unit.
8. The driving method of a pixel circuit according to claim 6, wherein the pixel circuit further includes a data voltage input terminal, a data writing unit, and a threshold voltage compensation unit; the control end of the data writing unit is electrically connected with the second scanning signal input end, the first end of the data writing unit is electrically connected with the first end of the driving unit, and the second end of the data writing unit is electrically connected with the data voltage input end; the control end of the threshold voltage compensation unit is electrically connected with the second scanning signal input end, the first end of the threshold voltage compensation unit is electrically connected with the control end of the driving unit, and the second end of the threshold voltage compensation unit is electrically connected with the second end of the driving unit; the driving method of the pixel circuit includes:
in the second stage, the data writing unit and the threshold voltage compensation unit are respectively controlled by the input signal of the second scanning signal input end to be conducted, and the data voltage input by the data voltage input end is written into the control end of the driving unit through the conducted data writing unit, the conducting driving unit and the conducting threshold voltage compensation unit.
9. The method for driving the pixel circuit according to claim 8, wherein the pixel circuit further comprises a light emission control signal input terminal, a first light emission control unit, and a second light emission control unit; the control end of the first light-emitting control unit is electrically connected with the light-emitting control signal input end, the first end of the first light-emitting control unit is electrically connected with the first end of the driving unit, and the second end of the first light-emitting control unit is electrically connected with the first voltage input end; the control end of the second light-emitting control unit is electrically connected with the light-emitting control signal input end, the first end of the second light-emitting control unit is electrically connected with the first end of the light-emitting unit, and the second end of the second light-emitting control unit is electrically connected with the second end of the driving unit; the driving method of the pixel circuit further includes:
in a third stage, the first light-emitting control unit and the second light-emitting control unit are respectively controlled by the input signal of the light-emitting control signal input end to be conducted, and the driving unit is used for driving the light-emitting unit to emit light.
10. A display panel comprising the pixel circuit according to any one of claims 1 to 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110085498.6A CN112669776B (en) | 2021-01-22 | 2021-01-22 | Pixel circuit, driving method thereof and display panel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110085498.6A CN112669776B (en) | 2021-01-22 | 2021-01-22 | Pixel circuit, driving method thereof and display panel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112669776A CN112669776A (en) | 2021-04-16 |
| CN112669776B true CN112669776B (en) | 2023-02-03 |
Family
ID=75414095
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110085498.6A Active CN112669776B (en) | 2021-01-22 | 2021-01-22 | Pixel circuit, driving method thereof and display panel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112669776B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113470574A (en) * | 2021-06-11 | 2021-10-01 | 云谷（固安）科技有限公司 | Pixel circuit, driving method thereof and display panel |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20190107229A (en) * | 2018-03-07 | 2019-09-19 | 삼성디스플레이 주식회사 | Pixel and display device using the same |
| KR102519364B1 (en) * | 2018-03-16 | 2023-04-10 | 삼성디스플레이 주식회사 | Gate driver, display apparatus including the same, method of driving display panel using the same |
| KR102514242B1 (en) * | 2018-06-20 | 2023-03-28 | 삼성전자주식회사 | Pixel and organic light emitting display device comprising the same |
| CN110246462A (en) * | 2019-07-26 | 2019-09-17 | 云谷（固安）科技有限公司 | A kind of pixel circuit and its driving method, display device and its driving method |
| CN111710299B (en) * | 2020-06-30 | 2022-01-07 | 厦门天马微电子有限公司 | Display panel, driving method thereof and display device |
-
2021
- 2021-01-22 CN CN202110085498.6A patent/CN112669776B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112669776A (en) | 2021-04-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10083658B2 (en) | Pixel circuits with a compensation module and drive methods thereof, and related devices | |
| CN108492770B (en) | Pixel compensation circuit, driving method thereof, display panel and display device | |
| CN107452338B (en) | A kind of pixel circuit, its driving method, display panel and display device | |
| US11227548B2 (en) | Pixel circuit and display device | |
| CN116580671A (en) | Display panel and display device | |
| US10984711B2 (en) | Pixel driving circuit, display panel and driving method | |
| CN111179854A (en) | Pixel driving circuit, driving method thereof and display device | |
| JP2020519925A (en) | Pixel driving circuit, pixel driving method, and display device | |
| CN109559686B (en) | Pixel circuit, driving method, electroluminescent display panel and display device | |
| CN107871471B (en) | Pixel driving circuit, driving method thereof and display device | |
| JP2019527844A (en) | Electronic circuit and driving method, display panel, and display device | |
| CN112102784B (en) | Pixel driving circuit, manufacturing method thereof and display device | |
| CN111739471A (en) | Display panel, driving method and display device | |
| CN113889039B (en) | Pixel circuit, driving method thereof, display substrate and display device | |
| CN106611586B (en) | Pixel-driving circuit, driving method, organic light emitting display panel and display device | |
| CN214377609U (en) | Pixel circuit, display panel and display device | |
| CN114270430B (en) | Pixel circuit, driving method thereof and display device | |
| US11501713B2 (en) | Pixel circuit, driving method thereof and display device | |
| CN114023263A (en) | Pixel circuit, driving method of pixel circuit and display panel | |
| CN113066439B (en) | Pixel circuit, driving method, electroluminescent display panel and display device | |
| CN112669776B (en) | Pixel circuit, driving method thereof and display panel | |
| CN108877684B (en) | Pixel circuit and driving method thereof, array substrate, display panel and display device | |
| CN113593475A (en) | Pixel circuit, driving method and display device | |
| CN113990261B (en) | Pixel circuit, driving method thereof and display panel | |
| CN115798411A (en) | Display panel, driving method thereof and display device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |